TURBOCHARGER 6J-1

SECTION 6J

TURBOCHARGER RPO LT3, LC2

VIN CODE M, 7

CONTENTS GENERAL DESCRIPTION Turbocharger Introduction ............................... 6J- 1 Turbocharger Definitions .................................. 6J-2 Turbocharger Operation .................................... 6J-4 Turbocharger Performance ............................... 6J-4 Intercooler Operation ........................................ 6J-4 Turbocharger Oil Supply .................................. 6J-4 Turbocharger Maintenance ............................... 6J-5 SYSTEM TROUBLESHOOTING

Troubleshooting Procedures ............................. 6J-5 Noise and Air Leak Check ............................... 6J-7 Turbocharger Unit Inspection .......................... 6J-8 FAILURE ANALYSIS AND

CORRECTIVE PROCEDURES ............... 6J-9 Major Causes of Turbocharger Failures ........... 6J-9

AND DIAGNOSIS

ON-CAR SERVICE 2.0 LITER-VIN M

Turbocharger ................................................. 6J-13 Wastegate Actuator ....................................... 6J- 14 Intake Manifold ............................................. 6J-15

GENERAL DESCRIPTION TURBOCHARGER INTRODUCTION

See Figures 1 thru 9

The turbocharger is basically an air compressor or air pump. It consists of a turbine or hot wheel, a shaft, a compressor or cold wheel, a turbine housing, a compressor housing, and a center housing which contains bearings, a turbine seal assembly and a compressor seal assembly.

Before entering into a discussion concerning the turbocharged engine system, we should review the basic characteristics of both the internal combustion engine and the turbocharger.

The internal combustion engine is classified as an air breathing machine. This means that the amount of power that can be obtained from a given displacement engine is determined by the amount of air that it breathes in a certain period of time and not by the amount of fuel that is used. This is because the fuel that is burned requires air with which it can mix to complete the combustion cycle. Once the aidfuel ratio reaches a certain point, the addition of more fuel will not produce more power, only black smoke. The more dense the smoke, the more the engine is being overfueled. Therefore, increasing the fuel delivery

Exhaust Manifold .......................................... 6J- 16 Turbocharger Oil Pipe and Hose

Routing ....................................................... 6J- 16 WastegateA3oost Pressure Test

Procedure .................................................... 6J-16 Specifications ................................................. 65- 17

Turbocharger ................................................. 6J- 18 Wastegate Actuator ....................................... 6J- 18 Intake Manifold ............................................. 6J- 18 Exhaust Manifold .......................................... 6J-19 Vacuum Hose & Line Routings ................... 6J-21 Oil Feed & Drain Pipes ................................. 6J-21 Control Assembly & Wastegate

Solenoid ...................................................... 65-2 1 WastegateA3oost Pressure Test

Procedure ................................................... 6J-21 Road Test 6J-22 Turbocharger Internal Inspection

Procedure 6J-22

3.8 LITER-VIN 7

.......................................................

I .................................................... Specifications ................................................. 6J-24

beyond the aidfuel ratio limit results only in excessive fuel consumption.

Turbochargers are installed on an engine to put more and denser air into the engine combustion chambers. Because of the increased volume and weight of compressed air more fuel can be scheduled to produce more horsepower from a given size engine. The turbocharged version of an engine will also maintain a higher level of power output than the non-turbocharged version when operated at altitudes above sea level.

TURBOCHARGER DEFINITIONS Turbine - The rotating wheel driven by exhaust

gasses also called hot wheel. Compressor - The rotating wheel driven by the

center shaft which is turned by the turbine. Also called the cold wheel.

Center Shaft - The shaft that connects the turbine to the compressor.

CHRA - Center Housing Rotating Assembly consists of: turbine, compressor, center housing, shaft, bearings and seals.

Wastegate - A valve that allows some of the exhaust gas to bypass the turbine wheel. This is done to limit boost.

6J-2 TURBOCHARGER

H400006J-GJ Figure 1 2.0 VIN M & 3.8 VIN 7 Engines

1 -TURBINE HOUSING 5-COM BUSTION

2-CENTER HOUSING CHAM BE R

6-LUBE OIL PUMP 3-COMPR ESSO R

HOUSING 7-EXHAUST MANIFOLD

4-INTAKE MANIFOLD

4200024J

Figure 2 Turbocharger Operation

a TURBINE OR HOT WHEEL 48652

Figure 3

Wastegate Actuator - A pressure sensitive servo that controls the wastegate.

Boost - Inlet manifold pressure higher than one atmosphere. (Positive Pressure.)

Coking - A condition that occurs when oil oxidizes on hot turbocharger interior surfaces.

Intercooler - A heat exchanger used to cool pressurized inlet air.

Wastegate Solenoid Valve - A pulse width modulated solenoid activated by the ECM that controls pressure to the wastegate actuator.

TURBOCHARGER 65-3

SHAFT 48653

Figure 4

II] COMPRESSOR OR COLD WHEEL 48654

Figure 5

48656 TURBINE HOUSING

Figure 6

~

48656 COMPRESSOR HOUSING

Figure 7

CENTER HOUSING 48657

Figure 8

6J-4 TURBOCHARGER

COMPRESSOR SEAL ASSEMBLY 4BOJ9 1

Figure 10

TURBOCHARGER OPERATION A turbocharger is an air pump designed to

operate on the normally wasted energy in engine exhaust gas. These gases drive the turbine (hot) wheel and shaft which is coupled to a compressor (cold) wheel which when rotating provides a high volume of air to the engine combustion chambers.

The turbocharger, although precision built, is basically a very simple but durable machine. It does, however, require maintenance and care as does any other piece of working machinery. A positive flow of clean lubricating oil is most critical.

The heat energy and pressure in the engine exhaust gas are utilized to drive the turbine wheel. The speed of the rotating assembly and output of the compressor wheel are controlled by the design and sizing of the turbine wheel and turbine housing and the wastegate assembly.

TURBOCHARGER PERFORMANCE A turbocharger is used to increase power on a

demand basis. As load on the engine is increased and the throttle is opened, more air-fuel mixture flows into the combustion chambers. As this increased flow is burned a larger volume of higher energy exhaust gas enters the engine exhaust system and is directed through the turbocharger turbine housing. Some of this energy is used to increase the speed of the turbine wheel. The turbine wheel is connected by a shaft to the compressor wheel. The increased speed of the compressor wheel allows it to compress the air it receives and deliver it to the intake manifold. The resulting higher pressure in the intake manifold allows a denser charge to enter the combustion chambers. The denser charge can develop more power during the combustion cycle.

The intake manifold pressure (boost) is controlled to a correct maximum value by an exhaust bypass valve (wastegate). The valve allows a portion of the exhaust gas to bypass the turbine wheel, thus maintaining a desired boost level. The wastegate is operated by a spring loaded diaphragm (actuator assembly) that

operates in response to boost pressure controlled by the wastegate solenoid to control maximum boost level.

(The wastegate solenoid is ECM controlled, for diagnosis and service procedures, see Section 6E.)

Some naturally-aspirated engines increase power by larger displacements which allows them to increase air-fuel consumption. Turbocharging allows increased air-fuel consumption and power without increasing displacement. A turbocharged engine is a finely tuned assembly which can adapt to increases in air-fuel consumption and the balanced increases in exhaust which occur under boost conditions. Any alteration to the air intake or exhaust system which upsets the air flow balance may result in serious damage to the turbocharged engine.

There are quite a number of benefits to be gained by turbocharging. Combustion of the fuel is more complete, cleaner, and takes place within the engine cylinders where its work is accomplished, because the turbocharger delivers an abundance of compressed air to the engine. The positive air pressure head (above atmospheric pressure) that is maintained in the engine intake manifold benefits the engine in several ways. During engine valve overlap (before the intake stroke starts), clean air is pushed across the combustion chamber scavenging remaining burned gases, cooling the cylinder heads, pistons, valves and the exhaust gas. The cleaner burning of the fuel plus the engine cooling which results helps to extend engine life.

INTERCOOLER OPERATION The 3.8L turbocharged engine uses an air to air

intercooler to lower the inlet air temperature and increase inlet air density. The cooler, denser inlet air allows a more dense aidfuel charge to enter the combustion chamber and increases power output by approximately 1 5 % .

As inlet air is compressed, its temperature increases. This heated, pressurized air is then routed thru the core of the intercooler. The intercooler is very similar in construction to a traditional radiator. Outside air passes thru the intercooler to lower the temperature of the inlet air in the core of the intercooler.

To increase the emciency of the intercooler at low vehicle speeds, a crankshaft mounted fan pulls air thru the intercooler.

TURBOCHARGER OIL SUPPLY An adequate supply of clean engine oil is essential

for cooling and lubrication to maintain the turbocharger bearing system. The rotating assembly (turbine wheel, connecting shaft, and compressor wheel) can attain speeds of 130,000 to 140,OOO RPM during boost. Interruption or contamination of the oil supply to the bearings (in the center housing) which support the rotating assembly can result in major turbocharger damage.

NOTICE: Any time a basic engine bearing (main bearing, connecting rod bearing, camshaft bearing) has been damaged in a turbocharged engine, the oil and oil filter should be changed as a part of the

TURBOCHARGER 65-5

repair procedure. In addition, the turbocharger should be flushed with clean engine oil to reduce the possibility of contamination.

Any time a turbocharger assembly is being replaced, the oil and oil filter should be changed as a part of the repair procedure.

TURBOCHARGER MAINTENANCE Good maintenance practices should be observed,

particularly regarding air and oil filtration, to maintain the service life and performance of a turbocharger. Years of experience has shown that the largest percentage of turbocharger failures are caused by oil lag, restriction or lack of oil flow and dirt in the oil. The second largest percentage is caused by foreign objects entering the compressor and/or turbine wheels.

1.

2.

3.

4.

- Dust or sand entering the turbocharger compressor housing from a leaky air inlet system can seriously erode the compressor wheel blades and will result in the deterioration of turbocharger and engine performance. The wearing away of the blades, if uneven, can induce a shaft motion which will pound out and eventually fail the turbocharger shaft bearings. Ingestion of sand or dust will also cause excessive wear on engine parts, such as pistons, rings, valves, etc. Entrance of large or heavy objects, bolts, nuts, rocks, tools, etc., will completely destroy the turbocharger and in many instances cause severe damage to the engine. Plugged or restricted air cleaner systems, resulting from poor maintenance procedures, will reduce air pressure and volume at the compressor air inlet and cause the turbocharger to lose performance. The restricted air cleaner and the resultant air pressure drop between cleaner and turbocharger can, during engine idle periods, cause oil pullover at the compressor end of the turbocharger. This would be a compressor end oil seal leak without a failure of seal parts. Proper servicing of the air cleaner system can prevent and correct the above problems. Dirt or foreign material, when introduced into the turbocharger bearing system by the lube oil, creates wear primarily on the center housing bearing bore sufaces. Contaminants imbed in the bearing surfaces and act as an abrasive cutting tool and eventually wear through. When bearing and bore wear becomes excessive, the shaft hub and either or both wheels will start to rub on the housings, causing the rotating assembly to turn slower. Turbocharger and engine performance will rapidly deteriorate from this point, and such indications as engine power loss, excessive smoke, excessive noise and the appearance of oil at either or both ends of the turbocharger could be noted. Contaminated and dirty oil is prevented when the lube oil system is properly serviced. A turbocharger should never be operated under engine load conditions with less than 30 psi oil pressure. A turbocharger is much more sensitive to a limited oil sumlv than an engine, due to the

high rotational speed of the shaft and the relatively small area of the bearing surfaces. Oil pressure and flow lag during engine starting can have detrimental effects on the turbocharger bearings. During normal engine starting, this should not be a problem. There are, of course, abnormal starting conditions. Oil lag conditions will most often occur during the first engine start after engine oil and filter change when the lubricating oil system is empty. Similar conditions can also exist if an engine has not been operated for a prolonged period of time because engine lube systems have a tendency to bleed down. Before allowing the engine to start, the engine should be cranked over until a steady oil pressure reading is observed, priming the lubricating system. The same starting procedure should be followed when starting an engine in cold weather as the engine oil can be congealed and take a longer period of time to flow. Turbocharger bearing damage can occur if the oil delay is in excess of 30 seconds, and much sooner if the engine is allowed to accelerate much beyond low idle rpm.

SYSTEM TROUBLESHOOTING AND DIAGNOSIS

First it should be emphasized that a turbocharger does not basically change the operating characteristics of an engine. A turbocharger is not a power source within itself. The. turbocharger’s only function is to supply a greater volume of compressed air to the engine so that more fuel can be burned to produce more power. It can function only as dictated by the flow, pressure and temperature in the engine exhaust gas.

A turbocharger cannot correct or overcome such things as malfunctions or deficiencies in the engine fuel system, timing, plugged air cleaners, etc. Therefore, if a turbocharged engine system has malfunctioned and the turbocharger has been examined and determined to be operational, proceed with trouble shooting as though the engine were non-turbocharged. Simply replacing a good turbocharger with another will not correct engine deficiencies.

All too frequently, serviceable turbochargers are removed from engines before the cause of malfunction has been determined. Always inspect and assess turbocharger condition before removal from the engine.

Inspect

See Figures 10 thru 13 1.

2.

Remove inlet and exhaust tubing from the turbocharger. Both wheels for blade damage caused by foreign material. The compressor wheel can be inspected by looking through the compressor housing inlet opening while holding throttle blade open. A light is necessary when examining the turbine wheel blade tips, as they are positioned inside the turbine housing and you have to look between the

6J-6 TURBOCHARGER

turbine wheel blades from the exhaust outlet end of the turbine housing.

3. The outer blade tip edges on both wheels, adjacent to their respective housing bores, and check for wheel rub.

4. Rotate the shaft wheel assembly by hand and feel for drag or binding conditions. Push shaft to side and rotate to feel for rub. It should turn smoothly. Lift both ends of the shaft up and down at the same time and feel for excessive journal bearing clearance. If clearance is normal, very little shaft movement will be detected. If a unit having normal bearing clearance of .003 to .006 is rocked up and down from one end only, the movement at end of shaft could be dial indicated at .015 to .020. Actual shaft end play is easily indicated without removing the turbocharger from the engine. If the shaft assembly rotates freely and no wheel damage, binding or rub has been noted, it can be assumed that the turbocharger is serviceable.

5 .

6.

CRACKED BLADE 121 BROKEN BLADE 486510

Figure 1 1

I i 3 BLADE DAMAGE FROM FOREIGN MATERIAL

486511

Figure 12

a NICK IN BLADE

Figure 13

SEVERELY BENT BLADES

486513

Figure 14

TROUBLESHOOTING PROCEDURES See Figures 15 and 16

To acquire confidence, ability and feel for accomplishing a turbocharger inspection, examine a new turbocharger as outlined. Compare inspection results between the new and used turbocharger. Turbocharger actual shaft end play and journal

bearing radial clearances can be checked as per instructions in the applicable turbocharger service manual.

CAUTION: Operation of the turbocharger without all normally installed inlet ducts and filters connected can result in personal injury and equipment damage from foreign objects entering the turbocharger. Each turbocharged engine system has its own

distinctive sound or noise level when operating. In

TURBOCHARGER 65-7

many cases, malfunctions can be detected when this noise level changes. if the noise level changes to a higher pitch it can indicate an air leak between air cleaner and engine or a gas leak in the exhaust system between turbocharger and engine. Noise level cycling from one level to another can indicate a plugged air cleaner, restriction in front of the turbocharger air inlet or heavy dirt build up in the compressor housing and on the compressor wheel. A sudden reduction in noise level with resultant black or blue smoke and excessive oil leakage indicates a complete failure.

NOISE AND AIR LEAK CHECK With the engine running, check the turbocharger

for uneven noise and vibration. This can indicate malfunction in the shaft wheel assembly. If suspicious conditions are noted, shut down the engine immediately to protect the turbocharger and engine from further damage.

Examine the turbocharger as per recommended inspection procedures. If any damage is evident, the turbocharger will have to be removed, cleaned and repaired or replaced as necessary.

If the turbocharger is assumed to be functional proceed with a check of the air system as follows:

inspect

Engine not running: 1. 2. 3.

Air cleaner for a restricted condition. All hose clamps for tightness. Intake manifold gasket and seals.

4. All hoses for cracks or deterioration. With engine running at idle:

1. Air tube and connections between air cleaner and turbocharger can be checked by lightly spraying with starting fluid. Leaks will be indicated by an increase in engine speed because the starting fluid will be pulled through the compressor wheel and into the engine. Air leaks between turbocharger and engine can be checked by feel and by an application of a light weight oil or soap suds on crossover tube, connections and hoses. Look for bubbles.

Exhaust gas leakage between engine block and inlet to turbocharger will also create a noise level change and reduced turbocharger performance. Check exhaust system as follows:

2.

Inspect

1. Manifold gaskets for leakage. 2. Manifold retaining bolts for tightness. 3. Manifold for cracks or porosity. 4. Turbocharger inlet gasket for leaks. 5. Turbocharger inlet flange bolts for tightness.

Exhaust gas leakage is detected by heat discoloration in the area of the leak.

TURBOCHARGER TROUBLESHOOTING

Figure 15

6J-8 TURBOCHARGER

BEARING TROUBLESHOOTING

PROBABLE CAUSE

Normal use

Con tam inated o i l (dirt in oi l) severely contaminated

0 0 (dirty oi l) prelube valve or o i l fi lter bypass valve

Pounded by eccentric shaft motion

Center housing bearing bores, rough finish

Metal or large particle o i l contamination

.Lack of lube, oi l lag, insufficient lube

Coking

Fine particles in oi l (contaminated oi l )

Rough bearing journals on shaft

Acceptable operating & maintenance

Engine oil & o i l filter(s) not changed frequently enough, unfiltered air en- tering engine intake, malfunction in

Foreign object damage, coked or loose housing, excessive bearing clearance due t o lube problem

Incorrect cleaning of ctr. hsg. during overhaul o f turbo. (wrong chemicals, bores sand or bead blasted)

Severe engine wear. i.e., bearing damage, camshaft o r lifter wear, broken piston

Low oi l level, high speed shutdowns, lube system failure, turbo plugged

Hot shutdowns, engine overfueled, re- stricted or leaking air intake

See contaminated o i l

Bearing journals not protected f rom sand or bead blast cleaning during overhaul

0 procedures

0

0 . 0

0 0

0

0 0

0

0 0 0

0 488516

Figure 16

TURBOCHARGER UNIT INSPECTION CAUTION: Operation of the turbocharger without all ducts and filters installed can result in personal injury or foreign objects damaging the wheel blades. Each turbocharger has its own distinctive sound

or noise level when operating. In many cases malfunctions can be detected when this noise level changes. If the sound of the turbo cycles up and down in pitch, check for an inlet air restriction or heavy dirt build up in the compressor housing and on the compressor wheel. If the noise level is a high pitch or whistling, look for an inlet air or exhaust gas leak. See "Noise and Air Leak Check".

With the engine shut off and the turbo stopped turning completely, make a visual inspection of the turbocharger and components. -

inspect

1. For loose ducting connections from the air cleaner to the turbo.

2.

3.

4.

5.

6.

7.

The cross-over duct from: the turbocharger to the intercooler, the intercooler to the throttle body. A loose duct can cause low power, noise, and oil loss through the compressor seals. The wheels of the turbo for impact damage from foreign objects from engine or ducting. For evidence of wheel contact against the housing walls. This would indicate internal bearing failure from loss of oil, contaminated oil, or imbalance. The shaft for free rotation. Push inward on one of the shaft wheels while you turn it by hand and feel for any rubbing or binding, do the same on the other side. The wheels should turn freely without contacting housings, backplate or shroud. Stiffness could indicate the presence of sludged oil or coking from overheating. The exhaust manifold and crossover pipe for loose connections and cracks. Oil drain line for restrictions. Any restriction can cause severe oil loss through the turbo seals. There may also be traces of burned oil on the turbine housing exterior.

TURBOCHARGER 6J-9

extra down time and expense. The initial and follow-on failure could also be of a type that could result in costly engine damage. The majority of turbocharger failures are found to be due to poor operating procedures, lack of, or improper preventive maintenance, or incorrect repair practices.

Although turbocharger durability and performance have greatly improved over the past few years, operational and environmental situations still exist that can result in turbocharger failure.

MAJOR CAUSES OF TURBOCHARGER FAILURE

There are many and varied causes of turbocharger failures. They can be grouped into four major categories: A. Lack of lubrication and/or oil lag. B. Foreign material in the lubricating system. C. Oil oxidation or breakdown. D. Foreign material in either the exhaust or air

induction systems.

~

HUB AREA 141 BEARING JOURNALS 12) BLADE 151 THREADED AREA

(31 OIL SEAL RING GROOVE 486516

Figure 17

. ....

3 BLADE 12] NUT FACE [31 BORE 486517

Figure 18

FAILURE ANALYSIS AND CORRECTIVE PROCEDURES

See Figures 17 thru 32

The importance of determining the exact cause of a turbocharger failure cannot be overemphasized. This determination should be made at the time of failure and should in all cases be corrected before a replacement turbocharger is installed.

Often, when a failed turbocharger is replaced with little or no thought given to the cause of the failure, there is a recurrence of the failure, resulting in

(

TURBINE WHEEL SHOWS HEAVY BACK FACE RUBBING

4B6J10

Figure 19

TURBINE WHEEL BLADES SHOW HEAVY RUBBING

4B6J19

Figure 20

6J-10 TURBOCHARGER

DEPOSITS OF BURNED OIL ON TURBINE WHEEL

4BBJ20

Figure 21

Causes of failure by type and corrective measures: A. Lack of lubrication and/or oil lag.

This type of failure occurs when the oil pressure and flow is insufficient to: a. Lubricate the journal and thrust

b. Stabilize the shaft and journal

c. Reach bearings before unit is

The turbocharger bearing’s need for oil increases as the turbocharger speed and engine load increases. Insufficient oil to the turbocharger bearings for a period as short as a few seconds during a heavy load cycle when shaft speed is high will cause bearing failures.

3. General precautions: When oil and/or filters are changed.

First engine startup after oil and filter change: crank engine, if possible, without starting until the filter and oil system is filled and steady oil pressure is shown on the gage, or, start and run the engine at low idle long enough to obtain a steady oil pressure reading; otherwise, a bearing failure may result due to lag or lack of lubrication. Priming the oil filters with clean oil will reduce engine cranking time.

Engine starting procedure after installing a turbocharger: a. Make certain that the oil inlet and

drain lines are clean before they are connected. If hoses are used, make certain that they have not hardened and that the inner lining has not deteriorated and started to flake off. If metal tubing is used, make certain that it is not restricted or collapsed. Make certain that the lube oil is clean and at operating level. The oil filter

1.

bearings.

bearings.

accelerated to high speeds. 2.

a.

4.

b.

should be filled with clean oil to minimize cranking time. Leave the oil drain line disconnected at the turbocharger and crank the engine over without starting until oil flows out of the center housing drain port. A steady oil flow indicates that air pockets are out of lube oil system. A funnel can be used to return oil to drain tube.

d. Connect the oil drain line, start the engine and operate at low idle rpm for a few minutes before loading engine.

c.

1 EXTREME EXAMPLE OF SAND EROSION

Figure 2 2

I 1 Zik - II] BROKEN COMPRESSOR WHEEL BLADE

Figure 2 3

B. Foreign material in the lubricating system: 1. Operating an engine with contaminated or

dirty oil and assuming that the oil filter will

the bearings can be costly to both the turbocharger and the engine. There are engine operating conditions when the oil competely bypasses the filter. Examples where the filter will be bypassed are:

remove all contaminants before they reach I

TURBOCHARGER 6J-11

NICKED COMPRESSOR WHEEL BLADE 4BBJ23

Figure 24

a THE BORE OF THE COMPRESSOR

488524 WHEEL HAS GROOVES

Figure 25

I I BLADE DAMAGE FROM FOREIGN MATERIAL

486J26

Figure 26

a. Cold weather when the engine oil is congealed - filter bypass can be open.

COMPRESSOR WHEEL BLADES SHOW HEAVY RUBBING

*98J28

Figure 27

~~

DAMAGED COMPRESSOR WHEEL BLADES

488527

Figure 28

2.

b. When oil filter is clogged - bypass can be open.

c. Filter bypass valve can stick in open or partly open position.

d. Filter element can be ruptured. e. Filter element improperly installed.

Contaminated or dirty oil will wear and fail turbocharger bearings much sooner than it will fail engine bearings, because the turbocharger shaft rotates at a much higher speed than the engine. When this type of failure is found in a turbocharger, the cause of oil contamination should be located and corrected before installing a replacement turbocharger. If this is not accomplished, a second turbocharger failure will soon occur, along with the possibility of extensive engine damage. In addition, if contaminants are large enough to plug the turbocharger internal oil passages, a lack of lubrication type of failure would result. Analysis of oil samples at oil filter change periods can help to prevent this type of

6J-12 TURBOCHARGER

failure. Oil and filter change periods should never be extended beyond the engine manufacturer’s recommended interval.

I I

COMPRESSOR WHEEL HAS TURNED ON THE SHAFT

486J26

Figure 29

a BEARING METAL DEPOSITED ON SHAFT

486529

Figure 30

C. Oil oxidation or breakdown:

Sludge accumulates in engine oil when oxidation and/or oil breakdown takes place. Sludge will affect turbocharger performance and life, and eventually engine life, when the sludge condition of lubricating oil becomes severe.

The spinning action of the turbocharger shaft throws the oil against the internal walls of the center housing where sludge particles stick and accumulate. In time, it builds up to a point that oil drainage from the turbine and journal bearing is affected. Turbine seal leakage then occurs. The deposited sludge at the turbine end may become coked (baked) and very hard because of the high temperatures in this area. This hard coke can flake off and start wearing the turbine end journal bearing and bearing bore, but turbine seal leakage usually occurs first. Shaft rotation may or may

not be affected. In many cases, the journal bearing clearances are unchanged. If turbine end oil leakage is encountered and it is suspected that sludge has built up at the turbine end of the center housing, center housing inspection can be made by looking through the oil drain opening. Heavy sludge build up will be seen on the shaft between the bearing journals and in the center housing from the oil drain opening on back to the turbine end when sludge and coked condition exists. In many cases, the turbocharger can be repaired by simply disassembling, cleaning and replacing a few kit-available parts.

important

0 When oil leakage is noted at the turbine end of the turbocharger, always check the turbocharger oil drain tube and the engine crankcase breathers for a restricted condition. Correct as necessary before working on the turbocharger. When a sludged engine oil condition is found, it is mandatory that the engine oil and oil filters are changed, using the factory recommended lubricating oil.

Sludge accumulation results from oxidation and/or breakdown of the engine oil. Primary causes are engine overheating, excessive combustion products from piston blowby, non-compatible oils, engine coolant leaking into the oil, the wrong grade or quality of oil and the lack of proper oil change intervals.

0

CONTAMINANTS IMBEDDED IN ALUMINUM BEARINGS

486530

Figure 3 1

D. Foreign material in either exhaust or air induction systems:

Foreign material which enters the exhaust or inlet air system will damage the wheels because of their extremely high speed. Small particles, such as sand, erode the leading edges of the blades. Large, hard particles tend to rip or tear the blades. Soft materials, such as shop towels or rubber items, roll the blades back, opposite the direction of the wheel rotation.

TURBOCHARGER 6J-13

GROOVE WORN IN BEARING 480531

Figure 32

If there has been a turbocharger failure caused by foreign material damaging the wheels, a thorough cleaning of the exhaust manifold and inlet air system is essential. It is extremely important to carefully service the turbocharger air inlet system. Be sure that no foreign objects are in the piping and that all connections are secure.

ON-CAR SERVICE

2.0 LITER VIN M Inspect TURBOCHARGER 0 For foreign material and determine its source.

See Figure 33 0 See Unit-Inspection.

important 0 The turbocharger is a precision built

Remove or Disconnect Raise car and suitably support. See Section OA. component and should be serviced by 1.

2. 3. 4.

5. 6. 7. 8. 9.

10. 11. 12. 13. 14. 15. 16. 17.

Lower fan retaining screw. Exhaust pipe. Bolt - Rear A/C support bracket, loosen remaining bolts. Bolt - Turbo support bracket to engine. Oil drain hose at turbo. Water return pipe Lower vehicle. Coolant recovery pipe and move to one side. Induction tube. Coolant fan. Oxygen sensor. Oil feed pipe at union. Water feed pipe Air intake duct and vacuum hose at actuator. Exhaust manifold retaining nuts. Exhaust manifold and turbocharger.

Disassemble 1. Oil feed pipe. 2. Oxygen sensor. 3. Actuator assembly. 4. Support bracket. 5. Exhaust elbow. 6. Turbocharger.

factory trained technicians only.

++ Assemble 1. Turbocharger to manifold. 2. Exhaust elbow. 3. Support bracket. 4. Actuator assembly. 5. Oxygen sensor. 6. Oil feed pipe.

lrpt Clean 0 Mating surfaces at cylinder head and manifold.

Install or Connect . 1.

2. Retaining nuts and washers.

Exhaust manifold and turbocharger with new manifold gasket.

Tighten __. 0 In sequence and to specifications

3. Oil feed lines. 4. 5. Oxygen sensor. 6. 7. 8. Induction tube. 9. Coolant recovery pipe.

Water feed & return lines

Air intake duct and vacuum hose to actuator. Cooling fan and upper screws.

6J-14 TURBOCHARGER

10. Raise car and suitably support. See Section OA. 11. Bolt - rear turbo support. 12. A/C support. 13. Oil drain hose. 14. Lower fan screw. 15. Exhaust pipe.

Inspect

0 For Intake leaks. 0 For Exhaust leaks.

STUD

BOLT VIEW A GASKET

NUT25N*M(18LBS.FT.) - STUD 2 5 N * M (18 LBS. FT.)

W&SHER

NUT 25 N * M ( 1 8 LBS. FT.)

SUPPORT BRACKET

EXHAUST OUTLET ELBOW

BOLT 5 0 N * M (37 LBS. FT.)

ADAPTER PLATE

H40008-8JJN Figure 33 Turbocharger Mounting

WASTEGATE ACTUATOR

Remove or Disconnect

. 2.

1. Induction tube.

Clip - Actuator rod to wastegate.

3. Vacuum hose.

4.

5 . Actuator assembly.

Retaining screws - Actuator to turbo.

/

NUT 5 0 N * M (37 LBS. FT.) WASTEGATE SOLENOID VALVE ASSEMBLY HARNESS ASSEMBLY

VIEW A

H4000sBJJN Figure 3 4 Wastegate Solenoid Valve Assembly &

Harness

U d PIPE PIPE

CLAMP FITTING

HOSE FITTING - NUT 24 N.M (1 7 LBS. FT.)

4001 1-8JJN Figure 3 5 Water Feed and Return Pipes

TURBOCHARGER 6J-15

Install or Connect

Actuator assembly and retaining screws.

Clip - Actuator rod to wastegate.

1. 2. Vacuum hose. 3. 4. Induction tube.

Inspect See Wastegate/Boost Pressure Test, steps 3 and 0 4.

INTAKE MANIFOLD See Figures 34 thru 38

rd INTAKE MANIFOLD

k=i GASKET W

NUT 24 N * M ( 1 7 LBS. FT.)

H4001O-BJJN

Figure 36 Intake Manifold

6200098J

Figure 37 Turbo Induction Tube and Hoses

Remove or Disconnect

1. Induction tube and hoses. 2. Wiring to throttle body, M.A.P. sensor and

wastegate. 3. PCV hose. 4. Hose, vacuum to throttle body.

5. Throttle cable and cruise control cable (if

6. Wiring, to ignition coil. 7. Manifold support bracket. 8. Wiring to fuel injectors. 9.

applicable).

Bolt rear generator bracket to generator. 10. Power steering adusting bracket. 11. Generator front adjusting bracket. 12. 13. Retaining nuts and washers. 14. Manifold and gasket.

Fuel lines to fuel rail inlet and regulator outlet.

0 If installing new manifold, transfer all necessary parts from old manifold to new manifold.

a GASKET ASSEMBLED VIEW 4001 2-BJ-JN

Figure 38 Air Cleaner and Intake Duct

0 Mating surfaces at cylinder head and manifold.

Install or Connect

1. 2.

3. Fuel lines. 4.

Intake manifold with new gasket. Retaining nuts and washers. Torque to 25 N - m (18 1b.ft.). f

I

Power steering and generator adjusting brackets.

Important

0 Any time the rear power steering adjusting bracket is loosened or removed, proper adjusting bolt torque sequence is essential for belt and

6J-16 TURBOCHARGER

5. 6. 7.

8. 9.

10.

EXt

pulley alignment, The rear adjusting bracket must be the last part secured to prevent distorting the accessory drive system to prevent the belt from coming off. See Section 3B for torque sequence.

Wiring to fuel injectors. Wiring to ignition coil. Throttle cable and cruise control cable (if applicable). Vacuum hoses and PCV hose. Wiring to throttle body, M.A.P. sensor and wastegate. Induction tube and hoses.

Inspect

0 For vacuum leaks. 0 For correct completion of repair.

AUST MANIFOLD See Figure 39

Remove or Disconnect

1. Turbo induction tube. 2. Spark plug wires. 3. Bolts and nuts turbo to exhaust manifold. 4. Retaining nuts, manifold and gasket.

lrpl Clean 0 Mating surfaces at cylinder head and manifold.

Install or Connect

1. Exhaust manifold with new gasket, torque nuts to 22 N-m (16 1b.ft.).

2. Turbocharger to exhaust manifold, torque nuts to 25 N*m (18 1b.ft.).

3. Spark plug wires. 4. Turbo induction tube.

Inspect 0 Exhaust leaks.

TURBOCHARGER OIL PIPE & HOSE ROUTING See Figures 40 thru 42

WASTEGATE/BOOST PRESSURE TEST PROCEDURE

Inspect

Actuator and wastegate mechanical linkage for damage. Hose from the throttle body to the wastegate solenoid and from the wastegate solenoid to the actuator assembly.

3. Attach hand operated vacuum/pressure pump J 23738, in series with component gage J 28474 to actuator assembly, replacing wastegate solenoid to actuator assembly hose.

4. Apply pressure to actuator assembly. At approximately 4 psi (3.5 to 4.5 psi) the actuator rod end should move .015", actuating the wastegate linkage. If not, replace the actuator assembly and check that opening calibration pressure is 4 psi. Crimp adjusment barrel on actuator rod to maintain correct calibration. Remove test equipment and reconnect wastegate solenoid to actuator assembly hose and clamps.

Important

0 Any service procedure or diagnosis to fuel injectors see Section 6E.

0 Do Not Apply 12 Volts Directly to Injector, this will result in damage to the injector and replacement.

1.

2.

5 .

1 -GASKET 2-EXPANSION JOINTS

3-MANIFOLD ASM. 4-BOLT & LOCKWASHER ASM.

5-STUD BOLT & LOCKWASHER

6-SH I E LD

FACE OUTWARD

27 N-rn (20 LB.FT.1

ASM. 27 N-rn (20 LB.FT.l

7-NUT22 N-rn (16 LB.FT.1

TORQUE NO. 2 & 3 MANIFOLD RUNNERS PRIOR TO NO. 1 & 4 RUNNERS

620015-BJ

Figure 39 Exhaust Manifold Asm. and Gasket

TURBOCHARGER 6J-17

BOLT6 N * M (51 LBS. IN.)

FITTING

131 CLIP

PIPE

CLIP

FITTING

BOLT H40009.6JJN

Figure 4 0 Turbo Oil Feed (RH)

VIEW A BRACKET - TURBO CHARGER

m B O L T 6 N * M ( 5 1 LBSIN.

NUT 22 N * M (1 6 LBS. IN.)

H40007-6JJN BRACKET

Figure 4 1 Turbo Oil Feed (LH)

H40006-6JJN

Figure 42 Turbo Oil Drain Hose

2.0 LITER TORQUE SPECIFICATIONS

Torque Nnm Lb.Ft. Turbocharger to exhaust manifold 25 18 Turbo outlet elbow to turbocharger 25 18 Turbo support bracket: Lower bolt 50 37 Retaining nut 25 18

65-18 TURBOCHARGER rorque N-m Lb.Ft. Exhaust pipe to elbow 25 18 Oil feed pipe to turbo 17 12 Oil feed pipe-union 17 12 Oil feed pipe to block 17 12

(both ends) 47 35 Oil drain hose

Exhaust manifold 22 16 Intake manifold 25 18 Throttle body 25 18

3.8 LITER-VIN 7 TURBOCHARGER-G CARLINE See Figures 43 thru 52

1.

2. 3. 4. 5. 6. 7. 8. 9.

10. 11. 12.

la

El

0

0

1. 2. 3. 4. 5. 6. 7. 8. 9.

10. 11. 12. 13. 14. 0

Remove or Disconnect

Air inlet hose from compressor section of turbocharger Compressor outlet pipe from compressor Turbocharger and oil breather heat shields Exhaust pipe from turbine outlet Oil breather vent from valve cover Oil feed line Turbocharger to bracket nuts (2) Turbine inlet from exhaust manifold Oil return line from turbocharger Vacuum lines from turbo wastegate actuator Intercooler outlet to throttle body pipe Turbocharger from engine

Inspect

All air passages for foreign material Turbocharger for wear, oil leaks, and bent blades on the turbine or compressor wheel

Install or Connect

Turbocharger to engine Start exhaust manifold to turbocharger bolts Start exhaust pipe to turbine outlet Oil return line Turbocharger to mounting bracket nuts Tighten exhaust pipe to turbocharger Tighten turbocharger to exhaust manifold Oil feed line Oil breather vent Vacuum lines to wastegate actuator Compressor outlet pipe Intercooler outlet pipe Turbocharger and oil breather heat shields Air inlet hose to compressor Boost pressure (see Wastegate/Boost Pressure Test Procedure)

WASTEGATE ACTUATOR

H Remove or Disconnect

1. Vacuum hose at actuator

2. Retaining clip at actuator rod to wastegate lever 3. Two bolts attaching mounting bracket to

compressor housing 4. Wastegate actuator

Install or ConnLct

1. Wastegate actuator 2. Two bolts attaching mounting bracket to

compressor housing 3. Retaining clip at actuator rod to wastegate lever 4. Vacuum hose at actuator

Adjust

0 Boost pressure (see WastegateDoost Pressure Test Procedure)

INTAKE MANIFOLD See Figure 44

H Remove or Disconnect

1. 2. 3.

4.

5.

6.

7.

8.

9. 10. 11. 12.

Drain coolant Air inlet tube Fuel line at fuel rail (inlet) and at pressure regulator (return) Injector wiring harness connectors (2) located just behind the coil Coolant temperature sensor wire connectors (2) located at the front of the manifold Coolant hoses: 0 Heater 0 Bypass 0 Upper radiator

0 EGR 0 Fuel pressure regulator 0 PCV

0 Throttle 0 Cruise 0 T.V.

Vacuum lines and hoses:

Cables from throttle body:

EGR vacuum control valve Ignition wires from spark plugs. Intake manifold bolts Intake manifold

p94 Clean 0 Intake manifold gasket and seal mating surfaces

TURBOCHARGER 65-19 1

27 N * M 120 LBS FT )

ELBOW HEAT SHIELD

27 N * M ( 2 0 LBS FT )

TURBO HEAT SHIELD

27 N * M (20 LBS FT

TURBO ASSEMBLY

Ir] TURBO MOUNTING BRACKET

I '

27 N * M 120 LBS FT )

50 N * M 137 LBS FT )

H40001-6J-6

Figure 43 Turbocharger Assembly

VIEW A

COOLANT TEMP. SWITCH 14) SEAL TEMP. FAN CONTROL 151 COOLANT TEMP. SENSOR

161 ECSSENSOR

Figure 44 Intake Manifold, Gasket and Dress Items

5. Coolant hoses: Install or Connect

Intake manifold gasket and end seals

Lower right-side turbo mounting bracket to intake and bracket support to plenum

0 Heater 1. 2. Intake manifold and attaching bolts 0 Bypass

0 Upper radiator 3.

6. Coolant temperture sensor wire connectors (2)

4. Vacuum lines and hoses: 7. Injector wiring harness connectors (2) 0 EGR 0 Fuel pressure regulator 0 PCV

8. Fuel line at fuel rail (inlet) and at pressure regulator (return)

9. Refill cooling system

6J-20 TURBOCHARGER

10. Cables to throttle body: 0 Throttle 0 Cruise 0 T.V.

11. EGR vacuum control valve 12. 13. Air inlet tube

EXHAUST MANIFOLD See Figures 45 thru 47

Left

Ignition wires from spark plugs

Remove or Disconnect

1. Raise car and suitably support. See Section OA. 2. Exhaust manifold to crossover pipe 3. Lower car. 4. Exhaust manifold to cylinder head bolts (6) 5. Exhaust manifold

EXHAUST CROSSOVER

(21 31 N m (22 LBS. FT.) G4000CBJ-G

Figure 45 Crossover Pipe 3.8L Turbo

EXHAUST MANIFOLD-G SERIES 12) BOLT 50 N.m (37 FT. LBS.) 131 CYLINDER HEAD

488562

Figure 47 Left Exhaust Manifold-G Carline

0 All mating surfaces and inspect for cracks or leaks

Install or Connect

Exhaust manifold to cylinder head bolts Raise car and suitably support. See Section OA. Exhaust manifold to crossover pipe

1. Exhaust manifold 2. 3. 4. 5. Lower car.

50 N.m (37 LBS. FT.)

Figure 46 Right Exhaust Manifold-G Carline G40006-6J-0

Right

'++ Remove or Disconnect

1. Exhaust pipe from turbocharger 2. Oxygen sensor wire 3. 4. Crossover from exhaust manifold 5. Lowercar. 6. Exhaust manifold to cylinder head bolts (6) 7. Exhaust manifold

Install or Connect

Exhaust manifold to cylinder head bolts Raise car and suitably support. See Section OA.

3 Raise car and suitably support. See Section OA.

1. Exhaust manifold 2. 3. 4. Crossover to exhaust manifold 5. Lower car. 6. Oxygen sensor wire 7. Exhaust pipe to turbocharger

Intercooler Removal

See Figure 52

3 Remove or Disconnect

1. Shroud from intercooler

TURBOCHARGER 6J-21

THROTTLE BODY

121 27 N m (20 LBS. FT.)

131 GASKET

G400056J-0

Figure 48 Throttle Body Attachment

PCV-BOOST GAGE HARNESS 121 4 N m (35 LBS. IN.) 131 EGR-PURGE-FUEL REG-HVAC-HARNESS

141 GASKET 151 27 N m (20 LBS. FT.)

040006-8J-G

Figure 49 Vacuum Hose and Line Routings

2. Intercooler inlet pipe from turbocharger 3. Intercooler outlet pipe throttle body and

intercooler 4. Intercooler to mounting bracket bolts (4) 5 . Intercooler

Install or Connect

Intercooler outlet pipe to intercooler and throttle body Intercooler inlet pipe to turbocharger

1. Intercooler to mounting brackets 2.

3. 4. Shroud to intercooler

4 OIL FEED PIPE 4 O I L DRAIN PIPE

O IL PRESSURE SWITCH

G40002.6J-G

Figure 50 Oil Supply 81 Return Line Routing

P

TURBO ASSEMBLY

CRANKCASE VENT PIPE

23 N*M I1 7 LBS. FT.)

INLET AIR ADAPTER - 131

\

GASKET

Figure 5 1 Inlet Air Adapter to Turbocharger H40002-6J-G

WASTEGATE/BOOST PRESSURE TEST PROCEDURE

Tools Required: J 23738 Vacuum/Pressure Pump J 28474 Compound Gage

Inspect

1. Wastegate-actuator mechanical linkage for

2. Hoses to actuator assembly 3.

damage.

Attach hand operated vacuum/pressure pump J 23738, in series with compound gage J 28474 to actuator assembly.

6J-22 TURBOCHARGER

64000865

Figure 52 Intercooler to Engine

4. Apply pressure to actuator assembly. 0 At approximately 13 1/2 psi the actuator

rod end should move .015 in., actuating the wastegate linkage.

0 If this does not occur, replace the actuator assembly and test for proper calibration.

0 Crimp the threads on actuator rod to maintain correct calibration.

5 . Remove test equipment and reconnect hoses as shown in the vacuum schematics.

6. An alternative method of checking wastegate operation is to perform a road test which measures boost pressure.

Tool Required:

1. Tee compound gage J 28474 into tubing between compressor housing and boost gage or MAP sensor switch with sufficient length of hose to place gage in passenger compartment.

ROAD TEST

J 28474 Compound Gage

CAUTION: Determine that hose and compound gage are in proper operating condition to avoid possible leakage of air-fuel mixture into passenger compartment during road test, possibly causing bodily injury.

2. 3.

Disconnect hose at Wastegate Solenoid and Plug Conditions and speed limits permitting, perform a zero to 40 or 50 mph wide open throttle acceleration.

0 Boost pressure as measured by the compound gage during road testing should reach 13-14 psi. If this does not occur, replace the actuator assembly and test for proper calibration.

0

TURBOCHARGER INTERNAL INSPECTION PROCEDURE See Figures 53 & 54

Inspect

0

0

0

0

For loose backplate to CHR4 bolts Tighten or replace as necessary. For missing gasket or "0" ring Check the journal bearings for radial clearance as follows:

Attach a dial indicator, with a two inch long, 3/4 to one inch offset extension rod to the center housing such that the indicator plunger extends through the oil outlet port and contacts the shaft of the rotating assembly. If required, a dial indicator mounting adapter can be used. Manually apply pressure, equally and at the same time, to both the compressor and turbine wheels, as required, to move the shaft away from the dial indicator plunger as far as it will go. Set the dial indicator to zero. Manually apply pressure, equally and at the same time, to both the compressor and

1.

2.

3. 4.

TURBOCHARGER 65-23

turbine wheels to move the shaft toward the dial indicator Dlunger as far as it will go.

0 Check for thrust bearing axial clearance as follows:

Note the maxhuGvalue on the indicaLor 1. dial. Make sure that the dial indicator reading noted is the maximum reading obtainable,

slightly in both directions while applying pressure. Manually apply pressure, equally and at the same time to the compressor and turbine

from the dial indicator plunger as far as it will go. Note that the indicator pointer returns exactly to zero.

make sure that the maximum clearance between the center housing bores and the shaft bearing 'diameters, as indicated by the maximum shaft travel, has been obtained.

which can be verified by rolling the wheels 2.

5 .

wheels, as required, to move the shaft away 3.

6. Repeat steps (2) through (9, as required, to 4.

7. If the maximum bearing radial clearance is less than 0.003 inch, or greater than 0.006 inch, replace CHRA and inspect housings.

NOTICE: Continued operation of a turbocharger having improper bearing radial clearance will result in severe damage to the compressor wheel and housing or to the turbine wheel and housing.

OFFSET ATTACHMENT - ADAPTER PLATE

8B8AS

Figure 53 Journal Bearing Clearance Check

Mount a dial indicator at the turbine end of the turbocharger such that the dial indicator tip rests on the end of the turbine wheel. Manually move the compressor wheel and turbine wheel assembly alternately toward and away from the dial indicator plunger. Note the travel of the shaft in each direction, as shown on the dial indicator. Repeat Step (2), as required, to make sure that the maximum clearance between the thrust bearing components has been obtained . If the maximum thrust bearing axial clearance is less than 0.001 inch, or greater than 0.003 inch, replace CHRA and inspect housings.

NOTICE: Continued operation of a turbocharger having an improper amount of thrust bearing axial clearance will result in severe damage to the compressor wheel and housing or to the turbine wheel and housing.

7 THRUST BEARING

TURBINE WHEEL

888Al-TZO

Figure 5 4 Thrust Bearing Clearance Check

24 TURBOCHARGER /

/’ 3.8 LITER TORQUE SPECIFICATIONS

TORQUE N-m LB. FT. Exhaust Manifold (Right) to Turbine

Exhaust Inlet Pipe +o Right Exhaust Manifold 31 23 Oil Feed Pipe to

CHRA to Turbine Housing 20 15 CHRA to Compressor Housing 17 13 Throttle Body to Intake Manifold 27 20 Oil Drain to CHRA 30 22 Support Bracket to Cylinder Head 50 37 Intake Manifold to Cylinder Head 60 44 Exhaust Manifold to Cylinder Head 50 37 Turbo to Support Bracket Nuts 27 20 Turbo Heat Shield to Support Bracket 27 20

Housing 27 20

Fitting at Turbo 10 7